This invention relates to vehicle seats.
It is known for example from British Pat. No. 1,070,381 to provide a vehicle seat comprising a seat part, a base part, a suspension interconnecting the seat part and the base part and forming a guide for the upward-downward movement of the seat part relative to the base part, a seat-support spring which acts upwardly on the seat part and which, under static load conditions, supports the seat part and the seat occupant at a ride position which is adjustable by varying the preload of the spring. In this seat, an Up-stop assembly was formed by an Up-stop device and an Up-stop abutment mounted respectively on parts of the seat which moved relatively to each other during rise and fall of the seat part, and said Up-stop device was movable relative to the part of the seat on which it was supported to vary the Up-stop position viz. the height of the seat part at which further upward movement of the seat part is prevented by mutual engagement of the Up-stop device and Up-stop abutment.
In such a seat however, the Up-stop device was movable at the will of the seat occupant and the correct adjustment of the Up-stop device depended on the seat occupant repeatedly moving his body weight on to and away from the seat and repeatedly adjusting the device until a desired Up-stop position relative to the ride position was achieved. A similar vehicle seat is described in British Pat. No. 1,414,157 but this suffers from the same drawbacks as that described above.
An object of the invention is to provide a seat of the type under consideration, in which an Up-stop device is easily adjustable, and in particular is adjustable automatically in response to the seat occupant raising or lowering the ride position of the seat part.